HD 4890 (Reference) VMem Mod needed

[largon]

The front/back pics from TPU you posted are of a Powercolor non-reference card which has different vMEM chips than VT242WF on AMD reference card. On the linked Powercolor card memory voltages (two of them) are controlled by those 8pin Upi-Semi chips, whose model I can't tell by those pics. One is on the backside below CF connectors and one on frontside just below the small fake copper (= aluminum) heatsink near the 6pin plugs.

Month or two ago, I managed to chip away literally a dust-spec size a chunk of a corner of one of the VT242WFs, while fumbling with a custom VRM heatsink. VT242WF is a square shaped CSP part around 3mm each side and the chipped corner is so small it's just barely and barely visible to the naked eye. One bloody small bit missing (match for size reference) and no-worky... Result was, the second memory phase broke = no image. I had to jury-rig both MvDD and MvDDQ to run from one single phase as both are 1.5v stock. But apparently there's a reason why the phases were non-unified to begin with... ¦P Anyways, the card works and is artifact free depending on game with underclocked memory (700-750MHz), but stock memory freq is totally unstable and artifacts heavily. Once I get blessed with enough inspiration, and repair my hot air-soldering iron I'll try to seperate the phases by hack-sawing an off board power phase to replace the broken one.